Vulnerable Dem senators balk at Obama’s gay marriage endorsement

Senate Democrats facing difficult reelections are breaking with President Obama’s endorsement of same-sex marriage, a sign the issue is politically dangerous in battleground states.

Sens. Jon Tester (Mont.) and Claire McCaskill (Mo.), the two most vulnerable Democratic senators, have declined to endorse Obama’s call for the legalization of gay marriage.

Sens. Joe Manchin (W.Va.), Bob Casey (Pa.) and Bill Nelson (Fla.), Democrats who have easier races but in states that could become more competitive by November, have also backed away from Obama’s stance.

They all represent states with constitutional amendments or laws banning same-sex marriage.

Senate Majority Leader Harry Reid (D-Nev.) predicted Thursday the Democratic Party would adopt a pro-gay marriage plank in its platform. While that may happen when delegates to the Democratic National Convention meet September in Charlotte, N.C., the party remains divided.

“Jon believes in civil unions for committed same-sex couples but in Montana a marriage is defined as between a man and a woman,” said Andrea Helling, Tester’s spokeswoman.

Montana is one of 30 states with constitutional amendments defining marriage as between one man and one woman, according to Human Rights Campaign, a group that promotes gay rights.